Soften yeast in warm water in a small bowl. Heat milk, sugar, salt and oil till warm (115-120 degrees). Turn into large mixing bowl. Add the yeast mixture. Stir in as much flour as you can.
Turn dough out onto lightly floured surface. Knead in enough remaining flour to make a moderately soft dough that is smooth and elastic (3-5 minutes total).
Shape into a ball in a greased bowl; turn once. Cover; let rise in warm place till double (about 1 hour). Punch dough down. Turn onto a floured surface. Cover; let rest for 10 minutes.
Roll dough on a lightly floured surface to an 18 by 12-inch rectangle. Spread melted margarine or butter over dough. Combine brown sugar and cinnamon; add raisins and nuts, if desired. Sprinkle sugar mixture over dough. Roll up from one of the long sides. Seal.
Slice into 12 pieces. Place, cut side down, in a greased 13 by 9 by 2-inch baking pan. Cover, let rise in a warm place till nearly double (30 mins.). Bake in a 350 degree oven for 25 to 30 minutes. Cool slightly. Remove from pans.
For icing, combine the powdered sugar, vanilla and enough water to make icing of drizzling consistency. Drizzle over warm rolls.
Makes 12 rolls.
